<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>闭包案例</title>
  </head>
  <body>
    <ul>
      <li>香蕉</li>
      <li>苹果</li>
      <li>梨子</li>
      <li>橘子</li>
    </ul>

    <script>
      var lis = document.querySelectorAll('li');
      for (var i = 0; i < lis.length; i++) {
        // 立即执行函数
        (function (i) {
          lis[i].onclick = function () {
            console.log(i);
          };
        })(i);
      }
    </script>
  </body>
</html>
